The manuscript is a compendium. It contains a tonary of invitatories (ff. 1-3), a small tonary of antiphons (ff. 3v-4v), a small tonary of mass chants (ff. 149-151), a gradual (ff. 151-228r), a sequentiary (ff. 228v-261), a second tonary of antiphons (ff. 264-267v), and several treatises on alchemy, astronomy and music theory. At least three different scribes were involved in the copying of these portions of the manuscript. All of the hands are twelfth-century Italian. The antiphoner (ff. 267v-450) is complete, and copied entirely by a single hand. (For a fuller discussion of the manuscript's contents and its scribes, please see the introduction to Glaeske, Piacenza, Biblioteca Capitolare 65, below.) The foliation is inconsistent: sometimes it is stamped onto the page or pencilled in, but at other times it is altogether lacking. The antiphoner contains several Offices that do not occur in any of the sources surveyed in Hesbert's >Corpus Antiphonalium Officii: chief among these are those for Sabinus, first bishop of Piacenza (ff. 371v-373v); the martyrs Gervasius and Protasius (ff. 387r-389r); Justina, patron of Piacenza (405v-407v); and the Finding of Antoninus (ff. 414r-416r). In the index, differentiae are assigned arbitrary numbers, and no attempt has been made to match this numbering system to that of either of the tonaries in the same manuscript. Each chant not found in CAO has been assigned an arbitrary number prefixed by "pia".